Sickle grinder



Aug. 28, 1956 A. E. THORSON SICKLE! GRINDER 2 SheetsSheet 1 Filed Feb. 1, 1955 Alvin 1 Thorson INVENTOR.

Aug. 28, 1956 A. E. THORSON SICKLE GRINDER 2 Sheeis-Sheet 2 Filed Feb. 1, 1955 Fig. 3

INVENTOR.

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Fig. 4

United States Patent SICKLE GRINDER Alvin E. Thorson, Corvallis, Mont.

Application February 1, 1955, Serial No. 485,372

1 Claim. (Cl. 51-36) This invention relates generally to sharpening apparatus and pertains more particularly to a machine specifically adapted for use in grinding or sharpening sickle blades.

A primary object of this invention is to provide an improved form of sickle blade grinder in which the operator may easily and rapidly grind a desired and particular spot on a sickle blade, the positioning of the blade and consequently the spot to be ground being manually controlled.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a top plan view of the sickle blade grinder;

Figure 2 is a partial front elevational view of the grinder;

Figure 3 is an enlarged transverse sectional view taken substantially along the plane of section line 3-3 of Figure 1;

Figure 4 is a vertical section taken substantially along the plane of section line 44 of Figure 3;

Figure 5 is an enlarged partial plan view taken substantially along the plane of section line 5-5 of Figure 2;

Figure 6 is a transverse sectional view taken substantially along the plane of section line 66 of Figure 5; and

Figure 7 is a partial plan view taken along the plane of section line 7-7 in Figure 3.

Referring now more particularly to the drawings, the reference numeral 10 indicates a base for the grinding machine which may include a series of circumferentially spaced and laterally projecting ears 12 which are apertured for the reception of lag bolts or the like for rigidly securing the base to a floor surface or the like. Centrally upstanding from the base 10 is a standard 14 at whose upper end is rigidly attached a platform assembly indicated generally by the reference character 16 and which, as will be readily apparent, is preferably formed of inverted channel-shaped configuration, although it is to be understood that other shapes and configurations could as well be suitably applied.

Rigidly secured, as by welding or the like, to one end of the platform 16 is an upright assembly indicated generally by the reference character 18 which will be seen to include the main body portion 20 and a horizontal portion 22, the latter being disposed in overlying relationship to the platform 16.

Secured to the opposite end of the platform 16 is a table assemblage 24 which, as shown in the preferred form, takes the configuration of an inverted elongated channel section 26 having removably secured to its opposite ends the wing or end extensions 28 and 39. For the purpose of removably securing the end extensions to the central section 26 of the table, triangles 32 and 34 2,760,31 l Patented Aug. 28, 1955 ice are rigidly secured, as by welding or other suitable means, to the opposite ends thereof such that their upper surfaces are disposed substantially flush with the upper surface of the central section 26. Setscrew members 36 and 38 are threadedly engaged through One side of the triangles 32 and 34 and bear against one leg of the extensions in the manner shown most clearly in Figure 6. A suitable lock nut member 40 is associated with each of the setscrews to maintain the desired pressure against the end extensions or wings. It is to be noted that the wings are of angle configuration, such as to nest snugly within the triangles, and the purpose of the extensions is to support the opposite ends of a .sickle blade 42 supported on the assemblage.

It will be noted that the upper surfaces of the platform 16 on the one hand and the center section 26 of the table 24 on the other hand are disposed in flush relationship, and that a substantially diamond-shaped opening 44 is provided in these two members, the purpose of which will be presently apparent. A stop bar 46 is bolted to the upper surface of the center section 26 by means of suitable fasteners 4S and for the purpose of adjusting this bar transversely of the section 26, elongated openings 50 are provided for the fasteners 4-8 in the manner shown most clearly in Figure 5..

Pivotally suspended from the portion 22 of the upright 18 are a pair of link members 52 and 54, the pin members 56 being provided for this purpose. The pin members 56 are received through one of a pair of apertures 58 in each depending leg 61' of the overlying portion 22 of the upright. Pivotally secured to the lower ends of the links 52 and 54, as by pins 62, is a carriage member 64, this member, in the preferred form, being formed from a pair of plates 66 interconnected by various means hereinafter described.

Thus, one end of the carriage assembly 64 is pivotally suspended from the upright assembly 18, whereas the opposite end thereof rotatably journals the sickle grinding wheel 68 in the manner shown. In this respect, it Will be noted that the forward or free ends of the plates 66 carry ball bearing members 70 rotatably mounting a transverse shaft 72 therein upon which the grinding wheel 68 is secured and to the free end of which is secured a pulley member 74. An electrical motor 76, including a base portion 78, is rigidly mounted upon a base plate member which is secured between and rigidly interconnects the plates 66. The motor shaft 82 carries a pulley 84 and the belt 86 is trained about the pulleys 74 and 84 such that rotary motion will be imparted to the grinding wheel 68. A shield 88 is secured between the plates 66 and its free end portion 90 overlies the grinding wheel 68 to prevent injury to an operator.

Also mounted adjacent the forward or free ends of the plates 66 is a generally U-shaped handle assembly 92, the free ends of whose legs 94 are rigidly secured to the plates 66, respectively, and whose bight portion 96 presents a hand grip for swinging the carriage assembly 64 back and forth under the control of the operator.

A support strap 100 is rigidly secured to the upper surface of the section 26 of the table assemblage and, as seen most clearly in Figure 3, the purpose of this support strap is to engage the undersurface of the sickle blade 42 such that the forward end thereof may engage upon the upper surface of the platform 16, and it Will be readily apparent that the stop bar 46 is so positioned that the forward ends of the teeth of the sickle blades are in substantial alignment with the rearward edge of the opening 44, see particularly Figure 7. Thus, when the carriage 64 is swung forwardly and downwardly to engage the sickle blade teeth, the grinding wheel 68 will not engage either the platform 16 or the table section 26 inasmuch as it will be permitted to project through the opening 44.

In this manner, since the sickle blade 42 is firmly supported by the stop bar 46 and by the table assemblage, while at the same time, it is easily slidable therealong, the sickle blade can be easily and rapidly positioned to perform a grinding operation at any desired one spot, the operator merely manipulating or sliding the sickle blade along the table assemblage during this operation. It may be desired to provide a rubber pad or support member on the upper surface of the platform 16 upon which to rest the grinding wheel 68 when it is not in use so as to avoid marring the surface of the platform.

To positively ensure rigid alignment of the carriage assembly 64 as it is moved into engagement with the sickle blade teeth, a pair of upright guide plates 110 and 112 are secured to opposite sides of the platform assemblage 16, these guide plates being disposed closely adjacent the outer sides of the plates 66 to prevent lateral movement of the carriage assembly.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling Within the scope of the appended claims.

What is claimed as new is as follows:

A machine for grinding sickle blades comprising, an

elongated table for supporting a sickle blade, a platform secured to and extending laterally from said table, an upright secured to the free end of said platform, a carriage overlying said platform, links pivotally con nected at opposite ends to said upright and the end of said carriage remote from the table, a grinding wheel journaled at the opposite end of said carriage, said table having a diamond-shaped aperture therein through which said grinding wheel can extend, a pair of upright guide plates on said platform disposed on opposite sides of said carriage to prevent lateral movement of said carriage and said grinding wheel, means for rotating said grinding Wheel, and a handle secured to said opposite end of the carriage for manual manipulation of the same, said table including a stop bar extending longitudinally thereof, said table further including removable adjustable end extensions adapted to support opposite ends of a sickle blade, and adjustable means for selectively securing said bar in various transverse positions relative to said table.

References Cited in the file of this patent UNITED STATES PATENTS 485,973 Netf Nov. 8, 1892 2,583,758 Webber Jan. 29, 1952 2,654,187 Ferrin Oct. 6, 1953 

